"Nitrous oxide (N20) emissions could almost double by 2050 if more aggressive action is not taken, undermining global efforts to curb climate change, the United Nations' Environment Programme (UNEP) said on Thursday."

"Commonly known as the 'laughing gas', nitrous oxide exists naturally in the atmosphere in trace amounts.

However, it is the third most potent greenhouse gas after carbon dioxide and methane due to human activities such as agriculture, fossil fuel combustion, waste water management and industrial processes.

N2O emissions into the atmosphere are currently around 5.3 million tones a year but this could almost double by 2050 if efforts to cut the gas are not increased, the UNEP report said."